The invention relates to a surgical device for pushing together a thread loop which is formed by a slip knot at the distal free end of the thread which can be displaced along the thread, with a displacing element which can be displaced on the thread in the direction of the loop.
Threads are extensively used in the surgical sector to join body parts to one another, to apply ligatures or to connect implant parts to one another or to the body of a patient. When doing so, it is customary to form the thread into a loop at its distal, free end and to connect the free end to the adjoining portion of thread by means of a slip knot, i.e. by means of a knot which can be displaced along the thread by constricting the loop, and which then remains in this position and cannot be pushed back. Such knots are known for example as “Roeder knots”.
For displacing the slip knot and for constricting the loop, it is known to dispose a displacing element on the thread, so that the surgeon can draw the loop together simply by securely holding the thread at its proximal end, remote from the loop, and displacing the displacing element on the thread in the direction of the loop, whereby the slip knot is displaced in the direction of the loop, and this leads to a drawing together of the loop.
In certain applications, the drawing together of the loop may cause damage if the loop is tightened too securely. In the case of conventional devices of this type, it was left to the skill of the operator to ensure that the loop was only ever tightened to an extent avoiding such damage, but this entails certain uncertainties.
It is an object of the invention to form a device of the generic type in such a way that excessive tightening of the loop is avoided with certainty.